Horizontal slider windows are commonly used in building construction and typically comprise a window frame with a relatively fixed sash and a relatively movable vent sash which moves horizontally while supported on a roller and guided in a guide channel in moving between open and closed positions. The method of sealing the areas around the perimeter of the vent sash has typically taken the form of installing felt or other similar weather stripping material so as to be engaged with the vent sash as it moves into the closed position. The window sash is normally held in partially open position merely by the friction in the support rollers and guides. Upon moving to the closed position, a locking mechanism is employed to secure the sash in the closed position.
This sealing arrangement is disadvantageous in that it is difficult to achieve properly installed weather stripping such as to insure good sealing contact. In addition, the resultant rubbing contact leads to wear of the contacting weather section of the stripping to the point where replacement is necessary. Furthermore, such weather stripping has often taken the form of felt material which is not entirely impervious to air infiltration such that under high wind conditions the seal performance is less than adequate.
These deficiencies of the typical sliding window construction have been appreciated and it has heretofore been proposed and implemented for an improved window construction of the general type which is disclosed in U.S. Pat. No. 2,790,211. In this construction, the sash is provided with a peripheral arrangement of a compressible seal such as a neoprene rubber mounted about the inside face of the vent sash. In the closed position, the window frame is arranged to have opposed facing surfaces corresponding to the compressible seal.
A cam mechanism is provided which acts at the four corners of the sash when operated to exert an inward force forcing the movable sash into a position compressing the peripheral seal against the facing window frame structure. The cam mechanism takes the form of a series of crank arms each having guide rollers which are simultaneously swinging by rotation of the crank arms to engage an inside guide surface of the window frame upon activation of an operating lever. The rollers are thereby moved overcenter to secure the window in the closed position with the seals compressed by the resultant inward movement of the sash.
In order to provide locking of the movable vent sash, a projection is provided carried by one of the crank arms, which projection interferes with the window frame in all vent positions except in a partially opened and the fully closed position. In the fully closed position, a recess comes into alignment with the projection which may receive the pin operation of the cam mechanism by the operating lever. This allows the cam mechanism to be operated to lock the movable vent sash in the fully closed position due to the positioning of the locking pin within the recess. A similar recess is provided in the vent open position.
This mechanism, while greatly enhancing the effectiveness of the window sealing, has the disadvantage of preventing activation of the cam mechanism is any but an open or the fully closed position of the vent sash. The casual user of the window mechanism will commonly attempt to activate the cam mechanism with the window in partially open positions, which attempt will tend to damage the operating components.
In addition, the vent sash, being supported on relatively low friction rollers, cannot be secured in other partially open positions, thus leaving the window unsecured if the movable sash is positioned in less than the fully open position.
Accordingly, it is an object of the present invention to provide such horizontal slider window construction of the type in which a camming mechanism is employed to force the movable sash into a position in which it is forced against the opposing surfaces of the window frame, to compress a seal extending about the periphery of an outside surface of the movable vent sash, which cam mechanism is operable in any position of the vent sash in the window frame such as to securely position the movable sash in any of its partially open positions.
It is yet another object of the present invention to provide such horizontal slider window construction in which the movable vent sash is securely locked in the fully closed position.
It is still another object of the present invention to provide such horizontal window slider construction which is simple and reliable in operation and is of rugged and trouble-free construction.